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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 1 |
| 1965 | 12 |
| 1966 | 27 |
| 1967 | 31 |
| 1968 | 30 |
| 1969 | 60 |
| 1970 | 45 |
| 1971 | 59 |
| 1972 | 83 |
| 1973 | 68 |
| 1974 | 84 |
| 1975 | 64 |
| 1976 | 47 |
| 1977 | 62 |
| 1978 | 54 |
| 1979 | 53 |
| 1980 | 69 |
| 1981 | 74 |
| 1982 | 90 |
| 1983 | 76 |
| 1984 | 80 |
| 1985 | 107 |
| 1986 | 82 |
| 1987 | 71 |
| 1988 | 80 |
| 1989 | 97 |
| 1990 | 89 |
| 1991 | 95 |
| 1992 | 80 |
| 1993 | 101 |
| 1994 | 110 |
| 1995 | 119 |
| 1996 | 123 |
| 1997 | 97 |
| 1998 | 123 |
| 1999 | 121 |
| 2000 | 153 |
| 2001 | 145 |
| 2002 | 172 |
| 2003 | 166 |
| 2004 | 181 |
| 2005 | 184 |
| 2006 | 156 |
| 2007 | 124 |
| 2008 | 143 |
| 2009 | 117 |
| 2010 | 106 |
| 2011 | 111 |
| 2012 | 104 |
| 2013 | 120 |
| 2014 | 131 |
| 2015 | 106 |
| 2016 | 96 |
| 2017 | 79 |
| 2018 | 77 |
| 2019 | 80 |
| 2020 | 59 |
| 2021 | 49 |
| 2022 | 33 |
| 2023 | 3 |